last year with Mr. Powlin we made some simple water bottle rockets after the ap exam. as we designed and built, we had a basic understading of what our rockets were supposed to look like, but for the most part were in the dark as far as the technical physics behind it. this is what i hope to explain. the common expression "this isnt rocket science" may have you expecting long equations with foreign symbols, however simple rocketry in its essence is counterintuitively pretty simple. for the type of rockets we made last year, only one condition is required for it to maintain its orientation, being that the center of mass must be higher on the rocket than the center of drag. This is why Mr. Powlin kept telling us its better to have more weight at the tip, the farthest point ahead of the center of drag, the fins. keep in mind that this only accounts for the meathod of stabilization using friction, as there are other ways to keep a projectile oriented, such as the use of gyroscopic forces, as used in bullets. PS, if you want to calculate more complicated aspects of rocketry, you will run into some pretty nasty equations.